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<FONT color="green">001</FONT>    // Copyright 2007 Waterken Inc. under the terms of the MIT X license<a name="line.1"></a>
<FONT color="green">002</FONT>    // found at http://www.opensource.org/licenses/mit-license.html<a name="line.2"></a>
<FONT color="green">003</FONT>    package org.waterken.factorial;<a name="line.3"></a>
<FONT color="green">004</FONT>    <a name="line.4"></a>
<FONT color="green">005</FONT>    import static org.ref_send.test.Logic.was;<a name="line.5"></a>
<FONT color="green">006</FONT>    <a name="line.6"></a>
<FONT color="green">007</FONT>    import org.ref_send.list.List;<a name="line.7"></a>
<FONT color="green">008</FONT>    import org.ref_send.promise.Eventual;<a name="line.8"></a>
<FONT color="green">009</FONT>    import org.ref_send.promise.Promise;<a name="line.9"></a>
<FONT color="green">010</FONT>    <a name="line.10"></a>
<FONT color="green">011</FONT>    /**<a name="line.11"></a>
<FONT color="green">012</FONT>     * Eventual invocation tests.<a name="line.12"></a>
<FONT color="green">013</FONT>     */<a name="line.13"></a>
<FONT color="green">014</FONT>    public final class<a name="line.14"></a>
<FONT color="green">015</FONT>    FactorialN {<a name="line.15"></a>
<FONT color="green">016</FONT>        private FactorialN() {}<a name="line.16"></a>
<FONT color="green">017</FONT>        <a name="line.17"></a>
<FONT color="green">018</FONT>        /**<a name="line.18"></a>
<FONT color="green">019</FONT>         * Runs a unit test.<a name="line.19"></a>
<FONT color="green">020</FONT>         * @param _ eventual operator<a name="line.20"></a>
<FONT color="green">021</FONT>         * @param n number to compute factorial of<a name="line.21"></a>
<FONT color="green">022</FONT>         */<a name="line.22"></a>
<FONT color="green">023</FONT>        static public Promise&lt;?&gt;<a name="line.23"></a>
<FONT color="green">024</FONT>        make(final Eventual _, final int n) {<a name="line.24"></a>
<FONT color="green">025</FONT>            int r = 1;<a name="line.25"></a>
<FONT color="green">026</FONT>            for (int i = n; i &gt; 0; --i) {<a name="line.26"></a>
<FONT color="green">027</FONT>                r *= i;<a name="line.27"></a>
<FONT color="green">028</FONT>            }<a name="line.28"></a>
<FONT color="green">029</FONT>            return _.when(Factorial.make(_, n), was(r));<a name="line.29"></a>
<FONT color="green">030</FONT>        }<a name="line.30"></a>
<FONT color="green">031</FONT>        <a name="line.31"></a>
<FONT color="green">032</FONT>        // Command line interface<a name="line.32"></a>
<FONT color="green">033</FONT>    <a name="line.33"></a>
<FONT color="green">034</FONT>        /**<a name="line.34"></a>
<FONT color="green">035</FONT>         * Executes the test.<a name="line.35"></a>
<FONT color="green">036</FONT>         * @param args  ignored<a name="line.36"></a>
<FONT color="green">037</FONT>         * @throws Exception    test failed<a name="line.37"></a>
<FONT color="green">038</FONT>         */<a name="line.38"></a>
<FONT color="green">039</FONT>        static public void<a name="line.39"></a>
<FONT color="green">040</FONT>        main(final String[] args) throws Exception {<a name="line.40"></a>
<FONT color="green">041</FONT>            final int n = args.length &gt; 0 ? Integer.parseInt(args[0]) : 4;<a name="line.41"></a>
<FONT color="green">042</FONT>            <a name="line.42"></a>
<FONT color="green">043</FONT>            final List&lt;Promise&lt;?&gt;&gt; work = List.list();<a name="line.43"></a>
<FONT color="green">044</FONT>            final Promise&lt;?&gt; result = make(new Eventual(work.appender()), n);<a name="line.44"></a>
<FONT color="green">045</FONT>            while (!work.isEmpty()) { work.pop().call(); }<a name="line.45"></a>
<FONT color="green">046</FONT>            result.call();<a name="line.46"></a>
<FONT color="green">047</FONT>        }<a name="line.47"></a>
<FONT color="green">048</FONT>    }<a name="line.48"></a>




























































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